1. Field of the Invention
Example embodiments of the invention relate to a display substrate, a display apparatus having the display substrate and a method of manufacturing the display substrate. More particularly, example embodiments of the invention relate to a display substrate based on a micro electro-mechanical system (“MEMS”), a display apparatus having the display substrate and a method of manufacturing the display substrate.
2. Description of the Related Art
Conventionally, display apparatuses such as a liquid crystal display (“LCD”), a plasma display panel (“PDP”), and a field emission display (“FED”) have been used, and a research on applying a new technology in the display apparatus field have been increased. Demands for the display apparatus based on a micro electro-mechanical system (“MEMS”) which has high light utilizing efficiency and low power consumption has been increased. A MEMS device is formed on a substrate such as a silicon substrate and a glass substrate, as a microstructure, and includes a driving unit outputting a mechanical driving power, and a semiconductor integrated circuit controlling the driving unit.
The display apparatus based on the MEMS includes a first substrate on which a reflective layer including at least one opening slot is disposed, and a second substrate having a shutter assembly including a digital micro shutter (“DMS”) which opens and closes the opening slot. The reflective layer may include a high reflective layer having a high reflectance and a low reflective layer having a low reflectance.
The high reflective layer may have a stacked structure to embody a high reflectance, but the reflectance may be decreased according to an emitting wavelength band, due to an error of a stacked thickness occurring in depositing a stacked layer.
In addition, the low reflective layer may be formed using a chrome (Cr)-based material to embody a low reflectance. In this case, an etching chamber may be polluted due to particles generated during an etching process. Furthermore, using a heavy metal such as chrome (Cr) may be restricted according to increasing demands for an environment-friendly product in the industrial field.
When the reflective layer is relatively thick due to the stacked structure, an error may be increased during a process of forming the opening slots.